Greeting cards, wrapping paper, magazines, brochures and other articles have been displayed by a wide variety of display racks. Many of the available display racks comprise a support apparatus and a series of retainers or compartments in which the displayed products rest. The retainers or compartments are either permanently attached to the support apparatus or attached to one another. One of the problems associated with display racks in which the retainers are permanently attached to the support apparatus is that the whole display rack must be replaced in the event that a single retainer is broken. Similarly, those display racks which have multiple retainers attached as a single unit often require that the entire unit be replaced when a single retainer is damaged. Even those display racks in which the retainers are reversibly joined to one another are inconvenient for the user because they require the user to disassemble and reassemble the display rack to replace a broken retainer.
Other types of display racks have retainers or compartments which can be individually attached to a support apparatus, such as a backboard. However, these display racks have the disadvantage that the retainers or compartments are attached to the support apparatus by inserting them at one of the side ends of the apparatus and sliding them into position on the apparatus. As is often the case, the side end may be adjacent to a wall or another display rack, making the side end inaccessible and requiring the entire display unit to be physically moved from its location to engage the new retainer.